A system and method for producing synthetic single or plural word messages was developed by Bruce Baker et al. and is disclosed in U.S. Pat. No. 4,661,916 to Baker et al. (the Baker '916 patent) issued on Apr. 28, 1987, the entire contents of which are hereby incorporated herein by reference. The system was directed to a linguistic coding system and keyboard for use by people with cognitive and/or physical impairments. The coding system and associated keyboard was used to store and access messages, which included words, plural word messages, phonemes, sentences, phrases, full names, letters, numbers, functions, or any combination thereof.
In such a system, the keyboard was coupled to a computer device, or was alternately part of the stand-alone entity which included a microprocessor, memory and display. The memory stored the messages for selective retrieval by the keyboard. The messages retrieved from the keyboard were then fed to a voice synthesizer, for example, which converted them through a loudspeaker to produce audible spoken messages. On this keyboard, associated with each of a plurality of keys, were polysemous (multi-meaning) symbols, also known as icons. By designating selected ones of the keys and their associated symbols or icons, selected stored messages or plural word messages (including but not limited to words, phrases and sentences) were accessed from the memory and then subsequently output.
With the system described in the Baker '916 patent, messages stored in the memory could be retrieved by activating a combination of symbol keys and other keys to vary the context of the polysemous symbols. Thus, a plurality of sentences could be selectively generated as a function of polysemous symbols in combination with other polysemous symbols. This allowed a user the ability to access thousands of words or messages based upon as little as one, two, or three keystrokes. Further, with symbols being polysemous, thousands of symbol sequences could be generated with only a small number of keys on a keyboard. Based upon ease of use of the system, the polysemous icons or symbols utilized, and the easily memorized symbol sequence combinations, such a system became ideal for many mentally and physically challenged users for whom spelling and typing, as well as speech itself, was extremely difficult.
The system of the Baker '916 patent allowed for an operator to go directly from thought to speech. This was possible because each key of the keyboard bore a central image or symbol which was polysemous and illustrated an important aspect of life and/or linguistic function. The keyboards could be varied depending on the intellectual level of the intended operator. Therefore, each keyboard could in itself be a language which was designed for or with a specific user.
Each of the polysemous symbols was developed to be rich in associations so that combinations of symbols could signal sentence or message ideas in the operator's memory. This enabled the generation of plural word or whole sentence messages by the activation of only a limited number of keys. The device allowed for the generation of many sentences or phrases and a large core vocabulary which could be easily retrieved from memory because of the ease with which the polysemous symbols on the keys portrayed the production of whole thoughts.
Although many people have learned to successfully use augmentative and alternative communication systems containing embodiments of the semantic compaction encoding techniques to communicate with very high levels of linguistic performance, some populations of children have had difficulty learning more advanced systems where the available language is effectively unlimited. Children with autism, in particular, may be overwhelmed by a large array of unfamiliar polysemous symbols and potential polysemous symbol sequences. Alternatively, they may perseverate on one symbol while a clinician is trying to provide structured instructional activities involving sequences associated with a different polysemous symbol.
The Baker '916 patent provided for embodiments that include a keyboard with a relatively large number of polysemous symbols suitable for individuals with relatively high cognitive and linguistic skills, and embodiments that included a keyboard with a relatively small number of polysemous symbols suitable for individuals with more significant cognitive, physical or linguistic impairments. An individual who has difficulty learning the system may benefit from a variety of structured self-paced instructional activities, which may help him/her learn foundational skills needed for accessing linguistic content in a polysemous symbol-based AAC system when the linguistic content of the system is organized into a rule-based linguistic architecture and similar patterns of polysemous symbol sequences may be used to produce groups of similar words with similar grammatical functions or parts of speech.
Previous embodiments of the Baker '916 patent and all subsequent patents have incorporated a plurality of polysemous symbols that were rich with association, and could be used sequentially to produce a plurality of previously stored messages using various polysemous symbol sequences. The association between a polysemous symbol sequence and a corresponding previously stored message often was not immediately obvious to an inexperienced operator learning to use a polysemous symbol system for communication, or to that person's instructor. Experienced operators have often needed to give explanations of the associations between polysemous symbol sequences and corresponding previously stored messages have often been required in instructional and clinical settings. Rationales to explain these associations have been provided in printed (hard copy) manuals that service providers could access who were teaching an inexperienced operator to use a polysemous symbol system for communication. Such hard-copy manuals can provide critical reference material for non-disabled service providers in instructional and clinical settings.